farm tractor The first steam-powered tractor on continuous tracks was completed by Fyodor Blinov 1888 Shielded metal arc welding By Nikolay Slavyanov 1888 Solar cell (based on the outer photoelectric effect) By Aleksandr Stoletov 1889 Three-phase induction motor By Mikhail Dolivo-Dobrovolsky 1889 Three-phase transformer By Mikhail Dolivo-Dobrovolsky 1889 Mosin–Nagant rifle By Sergei Ivanovich Mosin, the most produced rifle of the era 1890s 1890 Matryoshka doll By Sergey Malyutin and Vasily Zvyozdochkin 1890 Powered exoskeleton 1890 Chemosynthesis By Sergei Winogradsky 1891 Thermal chemical cracking Shukhov cracking process by Vladimir Shukhov and Sergei Gavrilov, the first cracking method 1891 Long-distance transmission of three-phase electric power By Mikhail Dolivo-Dobrovolsky at the International Electrotechnical Exhibition in Frankfurt am Main. This demonstration initiated the today's power grids. 1891 Three-phase hydroelectric power plant By Mikhail Dolivo-Dobrovolsky 1892 Viruses By Dmitri Ivanovsky 1894 Nephoscope By Mikhail Pomortsev 1895 Lightning detector / Radio receiver By Alexander Stepanovich Popov 1896 Thin-shell structure By Vladimir Shukhov 1896 Tensile structure By Vladimir Shukhov 1896 Hyperboloid structure By Vladimir Shukhov, see also Shukhov Tower 1897 Gridshell By Vladimir Shukhov 1898 Polar icebreaker A polar icebreaker is an icebreaker capable of operating in the polar waters with their vast and thick multi-year sea ice. The Russian icebreaker Yermak (named after Yermak the conqueror of Siberia) was the first icebreaker able to ride over and crush pack ice. It was built in England between 1897 and 1898 after Admiral Stepan Makarov's design and under his supervision. Between 1899 and 1911 Yermak sailed in heavy ice conditions for more than 1000 days. Starting from this vessel, Russia created the largest fleet of oceangoing icebreakers in the 20th and 21st centuries. 1899 Radiation pressure By Pyotr Lebedev 20th century Mstyora miniature 1901 Classical conditioning by Ivan Pavlov. Pavlov was awarded the Nobel Prize for his work in 1904. (Also referred to as "Pavlov's dog") 1901 Chromatography by Mikhail Tsvet 1902 Fire fighting foam Fire fighting foam is foam used for fire suppression. Its role is to cool the fire and to coat the fuel, preventing its contact with oxygen, resulting in suppression of combustion. Fire fighting foam was invented by the Russian engineer and chemist Aleksandr Loran in 1902. He was a teacher in a school in Baku, which was the main center of the Russian oil industry at that time. Impressed by the terrible and hardly extinguishable oil fires that he had seen there, Loran